Maths Terms for 11-13 Yr Olds

A whole number and a fractional part expressed as a common fraction.

Example: 1 2/3 (one and two thirds) is a mixed fraction. Also known as a mixed number.

For any integers a and b, a is a mulitple of b if a third integer exists such that a = b x c.

Example: 14 = 7 x 2, 49 = 7 x 7 and 70 = 7 x 10. So 14, 49 and 70 are all multiples of 7.

-21 is also a multiple of 7 since -21 = 7(-3).

The operation of combining two numbers to give a third number, the product. Example: 12 x 3 = 36 is a multiplication. Multiplication can be seen as the process of repeated addition.

Example: 3 x 5 = 3 + 3 + 3 + 3 + 3 = 15.

Multiplication is the inverse operation of division, and it follows that 7 ÷ 5 × 5 = 7.

A number less than zero. Example: -0.25. Where a point on a line is labelled 0 and equally spaced points to one side of it are labelled -1, -2, -3 etc, these, and the numbers represented by points between them, are negative numbers.

Negative numbers can also be used to represent direction, for example when describing the velocity (speed and direction) of a projectile. If a ball hits a wall and is said to move at 20 metres per second and then -2 metres per second, this just means that at some point it moves in the opposite direction it started moving (i.e. it bounces back off the wall at a speed of 2 metres per second.

1. In geometry, a plane figure in 2D composed of polygons which by folding and joining can form a 3D polyhedron.

2. Adjective meaning 'remaining after deductions'. Example: for businesses net profit is their profit after deducting all operating costs and expenses.

Any convention for recording mathematical ideas in writing and symbols. Example: Money is recorded using decimal notation e.g. £2.50.

A symbol used to denote a number. The Roman numerals I, V, X, L, C, D and M represent the numbers one, five, ten, fifty, one hundred, five hundred and one thousand. The Arabic numerals 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 are used in the Hindu-Arabic system giving numbers in the form that is widely used today.

An integer that cannot be divided neatly into two integers. Examples: 1, 3, 5, 7, etc.

A fixed point from which measurements are taken. See also Cartesian co-ordinate system. On a graph the origin is normally given by the point at which the x axis meets the y axis, at the co-ordinate (0,0).

A systematic arrangement of numbers, shapes, values or other objects according to a rule.